September ii, 1919] 



NATURE 



23 



this question. And, so far, it has not been 

 answered. 



(2) A conception of quite a different nature is 

 presented in the book by Dr. Roussy and his 

 colleagues on the treatment of the psychoneuroses 

 of war. Their work deals chiefly with those 

 "accidents d'ordre hysterique " which they 

 describe as the most important of the psycho- 

 neuroses observed during this war. A com- 

 parison of their book with such a treatment as 

 Dr. MacCurdy's in "War Neuroses " (recently re- 

 viewed in these columns) provokes the reflection 

 that a wider conception of the war psychoneuroses 

 than that held by these French authors seems to 

 be necessary if medical science is to learn all it can 

 from the experiences of war psychotherapy. The 

 book deals with the causation, treatment, and 

 prophylaxis of these hysterical disorders, and 

 discusses the recent "reflex," " dynamogenic, " 

 and "dyskinetic " theories of their nature. It 

 is clearly written and excellently illustrated. 



iOL'i? BOOKSHELF. 



Memoirs of the Boston Society of Natural History. 

 Vol. viii. No. 3. Monographs on the Natural 

 History of New England. The Turtles of New 

 England. By Dr. Harold L. Babcock. Pp. 

 327-431 + 16 pis. (Boston, Mass.: 1919.) 



This is a very interesting and excellently pro- 

 duced monograph dealing with seventeen species 

 out of sixty-one now recognised by American 

 authors. Considering that New England includes 

 the northern limit of distribution of the Chelonians 

 of eastern North America, this is a good number. 

 The author has collected most of the observations 

 published on the life-histories of these species, and 

 such a compilation is a valuable addition to the 

 fl- -icriptive and iconographic part of the work. 



»bjection may be taken to the title of the 

 iiiiuiograph, as the term "turtle" is usually 

 taken to apply to thoroughly aquatic Chelonians 

 only. As the author tells us, it has been sug- 

 gested that (i) all Chelonians of the land only 

 should be called tortoises; (2) all Chelonians of 

 fresh water should be termed terrapins ; and (3) all 

 Chelonians of the sea should be called turtles. It 

 is somewhat difficult to draw a limit between the 

 two first categories, and one does not quite like 

 the name " terrapin " to be bestowed on the soft- 

 slielled or river Chelonians, the Trionychidje. 

 Perhaps these might be termed river-turtles in 

 opposition to sea-turtles. 



The descriptive part is preceded by an intro- 

 iluction. in which the author deals with Chelonians 

 generally. Three statements call for criticism, 

 (i) The skull is stated to be more solid and com- 

 pact than in other reptilian orders; but what 

 about crocodiles ? (2) Some marine turtles are said 

 to be strictly herbivorous (p. 330); this can 

 only be meant to apply to the green turtle 

 [Chelone mydas), which is chiefly, but not 

 NO. 2602, VOL. 104] 



exclusively, so; and further on (p. 340) we 

 are told of a specimen in captivity greedily 

 taking large pieces of raw fish. Among the 

 terrapins, Batagur and Dermatemys are also 

 chiefly herbivorous. (3) Speaking of the longevity 

 of land tortoises, instances of existence for much 

 more than a century might have been given ; and 

 to the statement that Gilbert White's famous tor- 

 toise {Testudo ibera) lived nearly sixty years, " in 

 capitivity " should have been added. A still better 

 record for the same species is furnished by an 

 individual, on which the writer of this notice has 

 reported, that has been kept in Cornwall for 

 ninety-six years. G. A. B. 



LETTERS TO THE EDITOR. 



(The Editor does not hold himself responsible for 

 opinions expressed by his correspondents. Neither 

 can be undertake to return, or to correspond with 

 the writers of, rejected manuscripts intended for 

 this or any other part of Nature. No notice is 

 taken of anonymous communications.} 



Luminous Worms. 



The Rev. Hilderic Friend in his letter to Nature 

 of August 7 (p. 446) asks : " Is it possible that light 

 can mfluence Annelids in some way, and so facilitate 

 sexual processes?" He cites the affirmation of 

 Haugergues made in 177 1 that luminosity disappears 

 m certain cases after copulation. 



There is the other way of approaching the subject. 

 We know that the luminous earthworms, with which 

 Dr. Gilchrist has dealt in his recent paper, can be 

 stimulated to luminesce; so may we not ask: Is 

 it possible that sexual processes may facilitate the 

 excretion of the substance or substances to which 

 luminosity is due? 



We are acquainted with the fact that in other in- 

 vertebrate groups muscular contraction, due to a 

 stimulus to the nervous system, will expel the con- 

 tents of glands secreting the substances essential for 

 i the production of light. For example, we know that 

 i sometimes excitement due to the attack of enemies 

 j will cause phosphorescence in centipedes (Thomas 

 cited by Dahlgren, Journal of the Franklin Institute^ 

 , January, 1917, p. 85 of reprint). In a forthcoming 

 paper Dr. Brade-Birks and I shall indicate several 

 other ways in which the same result can be brought 

 j about among the Chilopoda. 



j A careful reading between the lines may show that 

 I fear, shock, and sexual processes each provide the 

 j stimulus to the nervous system which results in the 

 expulsion of the essentials of luminosity by a con- 

 traction of the muscles in the case cited by Mr. 

 Friend, and that if that stimulus were sufficient to 

 exhaust the store of secretion the animal mentioned 

 by Flaugergues would, of course, fail to exhibit 

 luminosity again until the secretion had had time 

 to re-accumulate. S. Graham Brade-Birks. 



16 Bank Street, Darwen, Lancashire. 



The National Union of Scientific Workers and Research. 



One of the chief aims of the National Union of 

 Scientific Workers is "to secure adequate endowment 

 for research and to advise as to the administration of 

 such endowment." A committee of active workers in 

 all the principal subjects has been appointed to con- 

 I sider methods of carrying out this object. While the 

 1 committee is agreed upon the general aim of making 



